#include<stdio.h>
 #include<malloc.h>
 #include <stdlib.h>
 typedef char DataType;
 #define STACK_SIZE 100

 typedef struct{                       
      DataType *top;
      DataType *base;
      int stack_size;
 }seqstack;

 void init(seqstack *s)
 {
      s->base=(DataType *)malloc(STACK_SIZE*sizeof(DataType));//
      if(!s->base) exit(-1);
      s->top=s->base;
      s->stack_size=STACK_SIZE;
 }

 int IsEmpty(seqstack *s)
 {
      return s->base==s->top;
 }

 int IsFull(seqstack *s)
 {
      return s->top-s->base==STACK_SIZE-1;//
 }

 void Push(seqstack *s,char ch)
 {
      if(IsFull(s))
      {
          printf("overflow\n!");
          exit(1);
      }
      else
          *s->top++=ch;
 }

 char Pop(seqstack *s)
 {
      if(IsEmpty(s))
      {
          printf("栈空\n");
          exit(1);
      }
      return *--s->top;
 }

 char Top(seqstack *s)// 取栈顶元素
{
      if(IsEmpty(s))
      {
          printf("栈空\n");
          exit(1);
      }
      return *(s->top-1);
 }

 void conversion(int a,int b)
 {
      int i;
      seqstack s;
      init(&s);
      while(a)
      {
          Push(&s,a%b);
          a=a/b;
      }
      printf("转换结果为:\n");
      while(!IsEmpty(&s))
      {
          i=Pop(&s);
          printf("%d",i);
          //当基数大于9时输出结果不对。改成printf("%x", i);可以实现16进制内的输出。改成printf("%c", (i < 10) i+'0' : i - 10 + 'A');可以实现36进制内的输出
      }
      free(s.base);
}

 int main(int argc,char *argv[])
 {
      int a,b;
      printf("请输入要被转换的十进制数\n");
      scanf("%d",&a);
      printf("请输入要转换成的进制数<2,8or16>\n");
      scanf("%d",&b);
      conversion(a,b);
      printf("\n");
      return 0;
 }
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